So I ordered the new battery & display. I have played with the online gear calculator but I'm not sure where to pick my shift points: upshifting from the small ring & downshifting from the the big. We have 52t x 34t chainrings and a 11t - 36t (11 speed) cassette. Could you early adopters suggest a place to start? Thanks.

1st thing is to view your gear configuration on the HTML5 Gear Calculator. <- I mapped your setup in this link. Your big and small rings have duplicated many ratios on the 11-36 cassette, so it doesn't really matter as much where you change over.

I would probably map the shift up from little to big ring at the 12t to the 18t. Synchro will perform the 3 cog shift to the 18t automatically. This shift will be a small ratio (and only a .4mph diff), so if you don't mind a bigger jump and want to be more aggressive with the move up to the big ring, you could map the shift to the 16t instead, which would be a 3.1mph diff. Going to the 16t is only 2 cogs diff, so the shifting would be a little quicker. I like small steps between gears, so my choice would be the first one.

Shifting from big to little, drop from the 32t to 24t which is only a 2 cog shift.

The above mapping will help make the most of your current chainring and only change between them when necessary (when you run out of usable gears in that ring).

I received the new DN110 battery and MT800 display and installed them today. It's mostly good news but there are some minor glitches.

First, there are only 2 options to get synchro shift.

Option 1. Synchro Shift without Wireless Connectivity
This requires both the new BT-DN110 battery and SC-MT800 display. I installed the new battery without the display and e-Tube couldn't make the Bluetooth connection. Although disappointing, this makes sense because the default shift mode is "Manual". The display allows the user to choose Manual, S1 (syncro) and S2 (synchro).

Option 2. Synchro Shift with Wireless Connectivity
This requires Option1 plus the new inline wireless unit (EW-WU111). The EW-WU111 replaces the D-Fly transmitter (EW-WU101), and adds Bluetooth to ANT+ connectivity. The EW-WU111 ($80) is usually externally mounted near the rear derailleur. This option allows a smartphone or tablet to update Di2 settings.

Even if you go for Option 2, it's better to do the 1st installation with a wired connection to your computer. It's easier to do the firmware updates and change the Bluetooth password. The BN110 needs to be updated to ver 4.3.4 and the MT800 requires ver 4.2.3.

As for the mapping, I suggest mapping S1 and S2 as full-synchro (eg. flat vs hilly terrain). The semi-synchro mode doesn't prevent cross-chains, and it's too easy to go big-big when doing a sweep of 2 or 3 gears. The other reason is that you can still manually change the front derailleur in full-synchro mode.

This brings up a quirk in the gear mapping (see attached). It's easy to change the cross over point in the small ring (eg. 34). I can get it to upshift to the big ring in gear 5 to 11 (smallest cog). However, I can only get a synchro shift from 50T to 34T when the cassette is in the 10th gear (2nd from largest cog). I can't seem to get the front derailleur to cross-over at a lower point (eg. 50 x 23). To get around this, I'll just manually shift to the 34T when approaching a steep climb or rolling terrain.

I only had time to go a short ride but the synchro feature is awesome! I'll do more testing to fine-tune the cross-over point.

A nice feature is that S1 or S2 will double-beep when the next gear change will shift the front derailleur.

I don't have a full road Di2 setup to test and so can't try this, but wondering what your multi-shift is set to? If less than 3, try setting it to 3 then go to your mapping and see if it allows you to drop from the big ring sooner.

With the XTR derailleurs, I'm pretty sure I was able to set the chainring changes to wherever I wanted, but still had to keep the cog diff within my multi-shift (3) setting.

I don't have a full road Di2 setup to test and so can't try this, but wondering what your multi-shift is set to? If less than 3, try setting it to 3 then go to your mapping and see if it allows you to drop from the big ring sooner.

With the XTR derailleurs, I'm pretty sure I was able to set the chainring changes to wherever I wanted, but still had to keep the cog diff within my multi-shift (3) setting.

My multi-shift setting is currently at 2 but I'll try it at 3. Another possibility that the Dura Ace 9070 mapping mimics aggressive riders. When I train in pacelines, I noticed that some riders will stay in the big ring even when they're in the big cogs (ie. a big-big combo). They don't want to risk a mis-shift when they have to accelerate quickly or stay in the paceline. So the Di2 mapping may reflect this shifting pattern. I wouldn't be surprised if the Ultegra 6870 on our tandem is more flexible in mapping the transition from big to small ring.

For current Di2 owners using the older XTR SC-M9050 display, the good news is that it will work with the new DT-DN110 battery. I tested the M9050 and it works just like MT800 display in handling synchro shifts. if you own the M9050, you just need the new battery. If you don't own the M9050, then the MT800 is a good replacement for the Junction A, and will offer Bluetooth & ANT+ connectivity if you buy the transmitter.

For current Di2 owners using the older XTR SC-M9050 display, the good news is that it will work with the new DT-DN110 battery. I tested the M9050 and it works just like MT800 display in handling synchro shifts. if you own the M9050, you just need the new battery. If you don't own the M9050, then the MT800 is a good replacement for the Junction A, and will offer Bluetooth & ANT+ connectivity if you buy the transmitter.

great news.

does the software block out non-approved chainring systems?

i.e., on my tandem we are running 39/53 chainring with 11-40 xt cassette with 6870GS RD with the roadlink and 6870FD and lastly the XTR 9050 display.

Edit: I should mention when I say "we are running" I mean we will be running. I haven't assembled the bike yet enough that I can plug it in and see anything in the software.

To do this tuning, can you just use the charger cable in the PC, or do you need the PCE1 interface?

i.e., on my tandem we are running 39/53 chainring with 11-40 xt cassette with 6870GS RD with the roadlink and 6870FD and lastly the XTR 9050 display.

Edit: I should mention when I say "we are running" I mean we will be running. I haven't assembled the bike yet enough that I can plug it in and see anything in the software.

To do this tuning, can you just use the charger cable in the PC, or do you need the PCE1 interface?

The e-Tube software won't block your 11-40 cassette.

When e-Tube starts up, it will "recognize" your Di2 hardware. In your case, e-Tube will accept your 2x11 drivetrain. The 39-53 crankset will be fine but you can only enter 11-32 as the largest cassette (the limit for a 6870 RD). The manual or synchro shifting will still work normally but the gear mapping will be incorrect. In other words, e-Tube will display the 39x32 as your lowest gear, when you're really using 39x40. You just have to calculate your own gear table and set the crossover points for downshifts (53 to 39) and upshifts (39 to 53T) for your preferred riding style.

BTW, get the new BT-DB110 battery rather than the older SM-BTR2 because the synchro function is worth the small price increase.

My multi-shift setting is currently at 2 but I'll try it at 3. Another possibility that the Dura Ace 9070 mapping mimics aggressive riders. When I train in pacelines, I noticed that some riders will stay in the big ring even when they're in the big cogs (ie. a big-big combo). They don't want to risk a mis-shift when they have to accelerate quickly or stay in the paceline. So the Di2 mapping may reflect this shifting pattern. I wouldn't be surprised if the Ultegra 6870 on our tandem is more flexible in mapping the transition from big to small ring.

For current Di2 owners using the older XTR SC-M9050 display, the good news is that it will work with the new DT-DN110 battery. I tested the M9050 and it works just like MT800 display in handling synchro shifts. if you own the M9050, you just need the new battery. If you don't own the M9050, then the MT800 is a good replacement for the Junction A, and will offer Bluetooth & ANT+ connectivity if you buy the transmitter.

You don't need a transmitter for blue tooth if You have the MT800 junction box. It uses bluetooth with a iPad or I phone to do all the programing. You can also connect it direct with a usb cord to the e tube software on a PC

You don't need a transmitter for blue tooth if You have the MT800 junction box. It uses bluetooth with a iPad or I phone to do all the programing. You can also connect it direct with a usb cord to the e tube software on a PC

When I paired my new DN110 battery to the MT800 display, I was hoping to get Bluetooth connection. I couldn't get it to work and just used an USB cable to update the firmware and setup synchro shifting

Did I make a mistake in the setup? Did you manage to get Bluetooth just by using the MT800?

The marketing material describes the MT800 "wireless compatible with ANT+ and Bluetooth", but not as a "transmitter". I talked to Competitive Cyclist and they said that the EW-WU111 inline transmitter is required. The WU111 replaces the SM-EWW01 D-Fly unit because it adds Bluetooth and internal placement (on carbon frames). This explanation makes sense because a MT800 (with transmitting ability) would make the new WU111 redundant.

When I paired my new DN110 battery to the MT800 display, I was hoping to get Bluetooth connection. I couldn't get it to work and just used an USB cable to update the firmware and setup synchro shifting

Did I make a mistake in the setup? Did you manage to get Bluetooth just by using the MT800?

The marketing material describes the MT800 "wireless compatible with ANT+ and Bluetooth", but not as a "transmitter". I talked to Competitive Cyclist and they said that the EW-WU111 inline transmitter is required. The WU111 replaces the SM-EWW01 D-Fly unit because it adds Bluetooth and internal placement (on carbon frames). This explanation makes sense because a MT800 (with transmitting ability) would make the new WU111 redundant.

yes I am able to communicate blue tooth to the MT800 without any other transmitters. I had some trouble getting it to pair the first time. I called shimano and they said if I connected wired for the first time and updated any firmware that it should pair better. I never did that but was able to finally get it to pair via bluetooth. I have not mapped my synchro shift points yet as we still have lots of snow. I think the EW_Wu111 is for those who don't want to have a display on the handlebars. I am using this new setup on our Calfee adventure frame tandem with XTR derailleurs and Ultegra hydraulic shifters and a triple setup.

yes I am able to communicate blue tooth to the MT800 without any other transmitters. I had some trouble getting it to pair the first time. I called shimano and they said if I connected wired for the first time and updated any firmware that it should pair better. I never did that but was able to finally get it to pair via bluetooth.

Thanks for the good news! My firmware is all updated so I'll try it again. It will be easier to use an iPad than a USB connection.

This brings up a quirk in the gear mapping (see attached). It's easy to change the cross over point in the small ring (eg. 34). I can get it to upshift to the big ring in gear 5 to 11 (smallest cog). However, I can only get a synchro shift from 50T to 34T when the cassette is in the 10th gear (2nd from largest cog). I can't seem to get the front derailleur to cross-over at a lower point (eg. 50 x 23). To get around this, I'll just manually shift to the 34T when approaching a steep climb or rolling terrain..

Just chiming in here to confirm this same issue and to add that I think Shimano may be doing this on purpose.

I experienced the same problem: cannot change the full synchro shift map to make the big to small front change happen any earlier. The only options are (in my case, on an 11-28 cassette) 28, or 25.

But I also set up a custom shift map - rather than adjusting the main profile - and in the software I was then able to change the shift map. But when I saved it, the custom setting had a big exclamation point next to it, and when I tried to add it as one of my main profiles (to overwrite one that was there) it told me that that gearing was not allowed.

I'm not sure why Shimano would do this, but in the current setup it seems it's not possible to change the full synchro shift map to shift from big to small in front any earlier than the 2nd biggest cog in back.

I don't like cross-chaining that much!

BTW, I'm doing all of the above with the latest firmware, newest battery, an sc-mt800 junction, and ultegra 6870 components -- all through the iPad E-TUBE app.

Just chiming in here to confirm this same issue and to add that I think Shimano may be doing this on purpose.

I experienced the same problem: cannot change the full synchro shift map to make the big to small front change happen any earlier. The only options are (in my case, on an 11-28 cassette) 28, or 25.

I called Shimano USA about the restriction on full synchro shift big ring to small ring (only after reaching 25T cog). They were surprised to hear about this issue but said that it's a firmware choice and not user-error. My guess is that the higher chain tension from a 50x25 combo reduces the chance of a dropped chain when the front & rear derailleur are coordinating a 16T drop (from 50T to 34T). Di2 may have an easier time with 14T drop (53T to 39T).

There are two threads with discussions on synchro setup and downshift issue:

I'll try to bypass this limitation by telling e-Tube that I'm using a 53-39 combo when I'm really using a 50-34. Even if that doesn't work, it's not a big deal for us. We ride a lot on hilly and rolling terrain, and we're more interested in the full synchro shift from 34T to 50T. With the MT800 display, it's easy to remember to downshift (50T to 34T) "manually" when we go from a flat section to a steep climb.

I called Shimano USA ...They were surprised to hear about this issue but said that it's a firmware choice and not user-error.

That was my sense as well – that they were doing this on purpose.

Quote:

My guess is that the higher chain tension from a 50x25 combo reduces the chance of a dropped chain when the front & rear derailleur are coordinating a 16T drop (from 50T to 34T). Di2 may have an easier time with 14T drop (53T to 39T).

Your logic is sound. But the weird thing is that I have put a couple thousand miles on a Di2 bike with a 50/34 crank (and 11/28 cassette) and it *happily* shifts from 50T to 34T from just about any rear cog imaginable. I've literally never had it drop the chain. So Shimano appears to be being very risk averse.

It's not a big deal for me, as I probably won't use full synchro anyway; I was just curious to test it out, and the current limitation is an odd one, since I assume a lot of people won't really be comfortable running all the way up to 25 in the big ring every time. Or, maybe people will just get used to it.

For me the bigger adjustment (mentioned in that other thread you linked to) is that when it drops from 50T to 34T it moves the front first, and there is quite a delay in shifting the rear. I'm a high cadence rider, and the front drop is too abrupt for me. But again, maybe I'll adjust.

Quote:

BTW, I got the SC-MT800 to connect to my iPad via Bluetooth.

Yes, me too: I did my entire setup on the iPad. I think I was lucky in that I didn't try this until some of the earlier bugs were worked out, and I read the instructions here and at WW about the passkey for bluetooth. That said, it worked really smoothly for me. And it's easier with the SC-MT800 because you can clearly see when the unit is in pairing mode, etc.

[QUOTE=mtseymour;19465643]My guess is that the higher chain tension from a 50x25 combo reduces the chance of a dropped chain when the front & rear derailleur are coordinating a 16T drop (from 50T to 34T). Di2 may have an easier time with 14T drop (53T to 39T).

I'll try to bypass this limitation by telling e-Tube that I'm using a 53-39 combo when I'm really using a 50-34. Even if that doesn't work, it's not a big deal for us. We ride a lot on hilly and rolling terrain, and we're more interested in the full synchro shift from 34T to 50T. With the MT800 display, it's easy to remember to downshift (50T to 34T) "manually" when we go from a flat section to a steep climb.

Quote:

Originally Posted by fronesis

That was my sense as well – that they were doing this on purpose.

Your logic is sound. But the weird thing is that I have put a couple thousand miles on a Di2 bike with a 50/34 crank (and 11/28 cassette) and it *happily* shifts from 50T to 34T from just about any rear cog imaginable. I've literally never had it drop the chain. So Shimano appears to be being very risk averse.

Chainring shifting 101:

The further inboard your rear cog, the more likely the chain will be guided inward over the inner chainring. ie: the chain will want to "walk" over the inner chainring if the chain angle is large enough to influence that mode.

Quote:

Originally Posted by fronesis

It's not a big deal for me, as I probably won't use full synchro anyway; I was just curious to test it out, and the current limitation is an odd one, since I assume a lot of people won't really be comfortable running all the way up to 25 in the big ring every time. Or, maybe people will just get used to it.

For a double ring setup, the big ring to 2nd cog chain angle is not that bad. That Shimano is not allowing customization of full synchro is yet another bozo choice on their part (other Di2 bozo decisions include having XTR FD as the only triple Di2 FD available).

Quote:

Originally Posted by fronesis

For me the bigger adjustment (mentioned in that other thread you linked to) is that when it drops from 50T to 34T it moves the front first, and there is quite a delay in shifting the rear. I'm a high cadence rider, and the front drop is too abrupt for me. But again, maybe I'll adjust.

Try setting your RD shift speed and see if that speeds it up somewhat.

I run our "semi-synchro" road/xtr drivetrain with the default shift speed and find the auto ring shift speed works adequately quickly for us. It would be interesting to compare a full road setup (Ultegra or DA) to see if the synchro shifting occurs any different.

I tried several things to get synchro shifting from 50T to 34T when the rear cassette is at 8 or 9 (with 11 being the biggest cog). These include entering 53-39 rings, 11-25 cassettes, and gear sweep. Nothing worked. My guess is that Shimano wanted to make sure that full synchro shift would work for aggressive riders, who tend to stay longer in the big ring. As more riders use synchro shift, Shimano will probably update the firmware to allow more flexible mappings.

Once my 2nd battery arrives, I'll be able to test full and semi-synchro on my single and tandem.

BTW, it's still easier to do the 1st installation with USB connection to a desktop. The e-Tube smartphone interface is different from the desktop version (eg. can't see the S1 and S2 mapping on the same screen), which is not ideal. However, the iPhone/iPad app is still more convenient for setting changes.

I received & installed the new battery & display. I notice that the new display has the Bluetooth logo on it. I connected to my computer via USB & downloaded the latest software. I'm no computer wiz (though I use them every day) but the Shimano user interface seems very awkward. I don't have it in front of me now but I was having a very hard time trying to set it up. I think I finally got it to recognize and accept the battery, display, both shifters and derailleurs. However, when I choose the Road type of bike, the options for the chainrings don't reflect what we have (52 x 34). Also, the cassette doesn't match what we have (11 x 36). Not sure this matters. When I thought I had it set up to at least test the Synchro function, the display shows an "M" (manual?) and the shifting is as before. I wasn't expecting to have to "hack" so much. I just want to have what I understand to be the full synchro function. I may give up and take it to an LBS where I hope one of the techs is Di2 savvy. Is this what it is like living on the bleeding edge?

I received & installed the new battery & display. I notice that the new display has the Bluetooth logo on it. I connected to my computer via USB & downloaded the latest software. I'm no computer wiz (though I use them every day) but the Shimano user interface seems very awkward. I don't have it in front of me now but I was having a very hard time trying to set it up. I think I finally got it to recognize and accept the battery, display, both shifters and derailleurs. However, when I choose the Road type of bike, the options for the chainrings don't reflect what we have (52 x 34). Also, the cassette doesn't match what we have (11 x 36). Not sure this matters. When I thought I had it set up to at least test the Synchro function, the display shows an "M" (manual?) and the shifting is as before. I wasn't expecting to have to "hack" so much. I just want to have what I understand to be the full synchro function. I may give up and take it to an LBS where I hope one of the techs is Di2 savvy. Is this what it is like living on the bleeding edge?

Your e-Tube software seems to be working properly but you're not using the specified or approved gearing. Di2 (or even mechanical shifting) won't work properly with a 18T gap at the front, so e-Tube won't show 52-34 as an option. It will show other approved chainring combos like 50-34, 52-36. You may get adequate results Di2 in manual mode, but you're asking for trouble by asking Di2 to do synchro shifting with a 18T gap. I strongly suggest that you change to 52-36 or 50-34.

Your rear cog of 11-36 (with Road Link) is also not supported by Shimano. Unlike the front, the unusually large cassette won't affect Di2. In e-tube, just choose 11-32 if you using Ultegra 6870 GS derailleur. The gearing table won't be correct but it doesn't affect your choice of cross-over points.

Remember to click "Complete Setup" to save all your changes to the Di2 hardware before you disconnect the USB.

When your tandem is ready to ride, the default on MT800 is "M" for manual. The display show light up when press the shifters. Double click on the bottom button to toggle between M, S1 and S2. Now you're ready to test the shifting.

Our bike was built by Tandems East. I requested the largest range that could be reliably shifted by Di2. I realize that the 18t jump in front is beyond the Shimano spec. I talked to Rob at Calfee & he says the 52t x 34t chainrings with the 11t x 36t cassette was their "gold standard". We don't have the Roadlink but a K-Edge derailleur cage. The bike shifts fine in manual mode but the 18t jump is pretty big. That is why I am so interested in Synchro shift. I often find that I stay in one ring or the other because the jump is so big. I have been encouraged by others on this forum to drop to 50t x 34t chainrings but we already find that we spinout at about 45 mph in the 52t x 11t. We also need the low end (age x hills). So, I think (hope) that I can make full synchro work but I realize that I am pushing the envelope. I guess that I don't see why if manually shifting works OK, why shouldn't synchro? Thanks again for your help.

I realize that I am pushing the envelope. I guess that I don't see why if manually shifting works OK, why shouldn't synchro?

As discussed earlier in this thread, it's possible to bypass the Shimano specs by entering false gearing info into e-Tube. For example, e-Tube can't verify whether you're using a 50-34 rather than 52-34 chainrings. It can only coordinate the movements of the derailleurs and the cross-over points for synchronized shifting. It's your choice to try the full or semi-synchro and see if either modes will improve your shifting experience.

Another question: What is the best way to hold the battery within the seatpost? The seatpost is carbon fiber about 22mm I.D. The battery came with a plastic split shell, some curved washers and a large retaining ring. None of these seem to help. I tried using electrical tape wrapped around each end of the battery & tried to slip it in the post. I want it tight enough to not rattle but not so tight that I can't remove it. I thought that the appropriate sized tapered rubber stopper with a hole and a split should hold it in place and still allow removal. Other suggestions? Thanks.

Another question: What is the best way to hold the battery within the seatpost? The seatpost is carbon fiber about 22mm I.D. The battery came with a plastic split shell, some curved washers and a large retaining ring. None of these seem to help. I tried using electrical tape wrapped around each end of the battery & tried to slip it in the post. I want it tight enough to not rattle but not so tight that I can't remove it. I thought that the appropriate sized tapered rubber stopper with a hole and a split should hold it in place and still allow removal. Other suggestions? Thanks.

Try setting your RD shift speed and see if that speeds it up somewhat.

I run our "semi-synchro" road/xtr drivetrain with the default shift speed and find the auto ring shift speed works adequately quickly for us. It would be interesting to compare a full road setup (Ultegra or DA) to see if the synchro shifting occurs any different.

Yes, I think that will make a difference. I will also experiment with altering the auto-adjust at the rear from 2 cogs to 1.

All that said, I did a hard ride this weekend (80 miles, 70 on reallly rough gravel) and I did adjust a bit to the semi-synchro. Just letting up the tiniest bit as I drop the front makes a noticeable difference.